/* * IBM ASM Service Processor Device Driver * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Copyright (C) IBM Corporation, 2004 * * Author: Max Asböck <amax@us.ibm.com> * */ #include <linux/sched.h>#include <linux/slab.h>#include "ibmasm.h"#include "lowlevel.h" static void exec_next_command(struct service_processor *sp); static atomic_t command_count = ATOMIC_INIT(0); struct command *ibmasm_new_command(struct service_processor *sp, size_t buffer_size){	struct command *cmd; 	if (buffer_size > IBMASM_CMD_MAX_BUFFER_SIZE)		return NULL; 	cmd = kzalloc(sizeof(struct command), GFP_KERNEL);	if (cmd == NULL)		return NULL;  	cmd->buffer = kzalloc(buffer_size, GFP_KERNEL);	if (cmd->buffer == NULL) {		kfree(cmd);		return NULL;	}	cmd->buffer_size = buffer_size; 	kref_init(&cmd->kref);	cmd->lock = &sp->lock; 	cmd->status = IBMASM_CMD_PENDING;	init_waitqueue_head(&cmd->wait);	INIT_LIST_HEAD(&cmd->queue_node); 	atomic_inc(&command_count);	dbg("command count: %d\n", atomic_read(&command_count)); 	return cmd;} void ibmasm_free_command(struct kref *kref){	struct command *cmd = to_command(kref); 	list_del(&cmd->queue_node);	atomic_dec(&command_count);	dbg("command count: %d\n", atomic_read(&command_count));	kfree(cmd->buffer);	kfree(cmd);} static void enqueue_command(struct service_processor *sp, struct command *cmd){	list_add_tail(&cmd->queue_node, &sp->command_queue);} static struct command *dequeue_command(struct service_processor *sp){	struct command *cmd;	struct list_head *next; 	if (list_empty(&sp->command_queue))		return NULL; 	next = sp->command_queue.next;	list_del_init(next);	cmd = list_entry(next, struct command, queue_node); 	return cmd;} static inline void do_exec_command(struct service_processor *sp){	char tsbuf[32]; 	dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf)); 	if (ibmasm_send_i2o_message(sp)) {		sp->current_command->status = IBMASM_CMD_FAILED;		wake_up(&sp->current_command->wait);		command_put(sp->current_command);		exec_next_command(sp);	}} /** * exec_command * send a command to a service processor * Commands are executed sequentially. One command (sp->current_command) * is sent to the service processor. Once the interrupt handler gets a * message of type command_response, the message is copied into * the current commands buffer, */void ibmasm_exec_command(struct service_processor *sp, struct command *cmd){	unsigned long flags;	char tsbuf[32]; 	dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf)); 	spin_lock_irqsave(&sp->lock, flags); 	if (!sp->current_command) {		sp->current_command = cmd;		command_get(sp->current_command);		spin_unlock_irqrestore(&sp->lock, flags);		do_exec_command(sp);	} else {		enqueue_command(sp, cmd);		spin_unlock_irqrestore(&sp->lock, flags);	}} static void exec_next_command(struct service_processor *sp){	unsigned long flags;	char tsbuf[32]; 	dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf)); 	spin_lock_irqsave(&sp->lock, flags);	sp->current_command = dequeue_command(sp);	if (sp->current_command) {		command_get(sp->current_command);		spin_unlock_irqrestore(&sp->lock, flags);		do_exec_command(sp);	} else {		spin_unlock_irqrestore(&sp->lock, flags);	}} /** * Sleep until a command has failed or a response has been received * and the command status been updated by the interrupt handler. * (see receive_response). */void ibmasm_wait_for_response(struct command *cmd, int timeout){	wait_event_interruptible_timeout(cmd->wait,				cmd->status == IBMASM_CMD_COMPLETE ||				cmd->status == IBMASM_CMD_FAILED,				timeout * HZ);} /** * receive_command_response * called by the interrupt handler when a dot command of type command_response * was received. */void ibmasm_receive_command_response(struct service_processor *sp, void *response, size_t size){	struct command *cmd = sp->current_command; 	if (!sp->current_command)		return; 	memcpy_fromio(cmd->buffer, response, min(size, cmd->buffer_size));	cmd->status = IBMASM_CMD_COMPLETE;	wake_up(&sp->current_command->wait);	command_put(sp->current_command);	exec_next_command(sp);}